Battery monomer and battery pack

Abstract

The utility model relates to the technical field of new energy batteries, and discloses a single battery and a battery pack, the single battery has a first direction, and the single battery comprises: a housing provided with an accommodating cavity and a pressure relief hole; the electrode assembly is arranged in the accommodating cavity; the anti-explosion valve comprises a fixing part, a first convex part and a valve body part, the fixing part is fixedly connected with the shell, the first convex part is connected with the fixing part and the valve body part, the valve body part is provided with a weak part, the electrode assembly is provided with a basic face close to the valve body part in the first direction, and the valve body part is provided with a first face deviating from the electrode assembly in the first direction; the maximum distance between the first face and the basic face is S1 mm, the fixing part is provided with a second face close to the electrode assembly in the first direction, the minimum distance between the second face and the basic face is S2 mm, and S1 is smaller than S2. And the distance between the first surface of the valve body part and the shell and the cover plate is increased, so that the safety boundary when a vehicle is scraped and knocked and damaged is improved, and the safety of the single battery is improved.

Description

Technical Field

[0001] This utility model relates to the field of new energy battery technology, and in particular to a battery cell and battery pack. Background Technology

[0002] Lithium-ion batteries are typically installed at the bottom of vehicles. During use, when the temperature is too high or the battery is punctured by a foreign object, thermal runaway can occur inside the battery, generating a large amount of high-temperature and high-pressure gas in a short period of time. Therefore, lithium-ion batteries are usually equipped with explosion-proof valves to quickly release internal pressure and improve the safety of the battery pack.

[0003] Existing lithium-ion batteries typically include a casing, an explosion-proof valve, and electrode assemblies. The casing comprises a housing and a cover plate, which together form a cavity. The electrode assemblies are housed within this cavity, and the explosion-proof valve is mounted on the cover plate or at the bottom of the housing. In recent years, when lithium-ion batteries are installed within battery packs, the explosion-proof valve is positioned towards the bottom of the pack. This ensures that in the event of thermal runaway, the high-temperature, high-pressure gas and flames will not be ejected towards the passenger compartment but rather towards the ground, providing some protection for the occupants.

[0004] However, with the explosion-proof valve facing the bottom of the battery pack, the explosion-proof valve area is a weak point of the lithium-ion battery. If the vehicle bottoms out during operation, the explosion-proof valve of the lithium-ion battery is easily damaged and leaks, increasing the risk of thermal runaway of the lithium-ion battery and easily causing a safety accident. Utility Model Content

[0005] The purpose of this invention is to provide a battery cell to solve the problem that the explosion-proof valve of lithium-ion batteries in the prior art is easily damaged by impacts; this invention also provides a battery pack using this battery cell.

[0006] To achieve the above objectives, this utility model provides a battery cell having a first orientation, the battery cell comprising:

[0007] The outer casing has a receiving cavity and a pressure relief hole communicating with the receiving cavity;

[0008] Electrode assembly is disposed in the receiving cavity;

[0009] An explosion-proof valve is provided, which covers the pressure relief hole. The explosion-proof valve includes a fixing part, a first protrusion, and a valve body. The fixing part is fixedly connected to the outer shell. The valve body is located on the side of the fixing part close to the electrode assembly along the first direction. The first protrusion connects the fixing part and the valve body. The valve body has a weak part. The electrode assembly has a base surface close to the valve body along the first direction. The valve body has a first surface away from the electrode assembly along the first direction. The maximum distance between the first surface and the base surface is S1 mm. The fixing part has a second surface close to the electrode assembly along the first direction. The minimum distance between the second surface and the base surface is S2 mm, satisfying: S1 < S2.

[0010] In some embodiments, the valve body includes a valve body and a reinforcing portion disposed on the valve body, the valve body is connected to the first protrusion, and the weak portion is disposed on the valve body.

[0011] In some embodiments, the reinforcing portion includes a recess and a second protrusion, the recess being located on the side of the valve body close to the fixing portion along the first direction, and the second protrusion connecting the recess and the valve body.

[0012] In some embodiments, along the first direction, the distance between the recess and the valve body is L1 mm, and the distance between the fixing part and the valve body is L2 mm, satisfying: L1 < L2.

[0013] In some embodiments, the reinforcing portion further includes a second reinforcing rib, which is disposed on the second protrusion and connects the recess to the valve body.

[0014] In some embodiments, the reinforcing portion further includes a third protrusion and a raised portion, the raised portion being disposed on the side of the valve body away from the fixing portion along the first direction, and the third protrusion connecting the raised portion and the valve body.

[0015] In some embodiments, the reinforcing part further includes a contoured boss that protrudes toward the electrode assembly along the first direction, and the contoured boss is either a conical platform or an arc-shaped platform.

[0016] In some embodiments, the explosion-proof valve further includes a recess and a second protrusion, the recess being located on the side of the valve body portion close to the fixing portion along the first direction, and the second protrusion connecting the recess and the valve body portion.

[0017] In some embodiments, along the first direction, the distance between the recess and the valve body portion is L1, and the distance between the fixing portion and the valve body portion is L2, where L1 < L2.

[0018] In some embodiments, the explosion-proof valve further includes a second reinforcing rib, which is disposed on the second protrusion and connects the recess to the valve body portion.

[0019] In some embodiments, the explosion-proof valve further includes a third protrusion and a raised portion, the raised portion being disposed on the side of the valve body portion away from the fixed portion along the first direction, and the third protrusion connecting the raised portion and the valve body portion.

[0020] In some embodiments, the explosion-proof valve further includes a first reinforcing rib, which is disposed on the first protrusion and connects the fixing portion and the valve body portion.

[0021] In some embodiments, the first protrusion is a tapered protrusion or an arc-shaped protrusion.

[0022] In some embodiments, the weak portion includes grooves extending around the first direction, the grooves being discontinuously distributed.

[0023] In some embodiments, the housing includes a shell and a cover plate fixedly connected to the shell, the shell and the cover plate forming the receiving cavity, and one of the shell and the cover plate is provided with the pressure relief hole, the pressure relief hole penetrating the shell or the cover plate along the first direction.

[0024] This utility model also provides a battery pack, including the battery cells described in any of the above technical solutions.

[0025] Compared with the prior art, the beneficial effects of this embodiment of the battery cell and battery pack are as follows: The explosion-proof valve is formed by a fixing part, a first protrusion and a valve body part. After the fixing part is fixedly connected to the outer shell or cover plate, since the valve body part is located on the side of the fixing part close to the electrode assembly along the first direction, and the maximum distance S1 between the first surface and the base surface of the electrode assembly is less than the minimum distance S2 between the second surface and the base surface of the electrode assembly, the valve body part is raised relative to the fixing part, and the distance between the valve body part and the outer shell is increased, thereby improving the safety boundary when the vehicle is scraped or damaged. This makes the valve body part, which is a weak part on the battery cell, less likely to be impacted, reducing battery cell damage and leakage, and improving the safety of the battery cell. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the structure of the explosion-proof valve of the battery cell of this utility model when it is assembled at the bottom of the housing;

[0027] Figure 2 This is a schematic diagram of the structure of the explosion-proof valve of the battery cell of this utility model when it is assembled on the cover plate;

[0028] Figure 3 This is a schematic diagram of the explosion-proof valve of the battery cell of this utility model;

[0029] Figure 4 yes Figure 3 A bottom view of the explosion-proof valve;

[0030] Figure 5 yes Figure 4 A cross-sectional view of the explosion-proof valve along line AA;

[0031] Figure 6 yes Figure 5 A partial assembly diagram of the explosion-proof valve and the electrode assembly at point M, magnified;

[0032] Figure 7 This is a schematic diagram of the structure of one embodiment of the upper reinforcing part of the explosion-proof valve of the battery cell of this utility model;

[0033] Figure 8 yes Figure 7 A bottom view of the explosion-proof valve;

[0034] Figure 9 yes Figure 8 A cross-sectional view of the explosion-proof valve along line BB;

[0035] Figure 10 yes Figure 9 A magnified schematic diagram of the explosion-proof valve at point N;

[0036] Figure 11 yes Figure 7 A schematic diagram of the explosion-proof valve with the first and second reinforcing ribs;

[0037] Figure 12 This is a schematic diagram of another embodiment of the reinforcing part on the explosion-proof valve of the battery cell of this utility model;

[0038] Figure 13 yes Figure 12 A bottom view of the explosion-proof valve;

[0039] Figure 14 yes Figure 13 A cross-sectional view of the explosion-proof valve along line CC;

[0040] Figure 15 This is a schematic diagram of the structure of the upper reinforcing part of the explosion-proof valve of the battery cell of this utility model, which is a contoured boss;

[0041] Figure 16 yes Figure 15 A cross-sectional view of an explosion-proof valve;

[0042] Figure 17 This is another structural schematic diagram of the explosion-proof valve of the battery cell of this utility model, which is a contoured boss.

[0043] Figure 18 yes Figure 17 A cross-sectional view of an explosion-proof valve.

[0044] In the figure, 1 is the outer shell, 11 is the housing, 12 is the cover plate, 13 is the receiving cavity, 14 is the pressure relief hole, 2 is the electrode assembly, 3 is the explosion-proof valve, 301 is the fixing part, 3011 is the second surface, 302 is the first protrusion, 303 is the valve body, 3031 is the first surface, 304 is the weak part, 305 is the concave part, 306 is the second protrusion, 307 is the second reinforcing rib, 308 is the third protrusion, 309 is the raised part, 310 is the first reinforcing rib, 320 is the valve body, 330 is the reinforcing part, 340 is the contour boss, and Z is the first direction. Detailed Implementation

[0045] The specific embodiments of this utility model will be described in further detail below with reference to the accompanying drawings and examples. The following examples are used to illustrate this utility model, but are not intended to limit its scope.

[0046] A preferred embodiment of a battery cell of this utility model is as follows: Figures 1 to 18 As shown, the battery cell includes a housing 1, an electrode assembly 2, and an explosion-proof valve 3. The electrode assembly 2 is arranged inside the housing 1, and the housing 1 is used to protect the electrode assembly 2. The explosion-proof valve 3 is used to quickly release pressure in the event of thermal runaway of the battery cell. The battery cell has a first direction Z. In this embodiment, the battery cell is a prismatic battery, and the first direction Z is the height direction of the battery cell.

[0047] The outer casing 1 has a receiving cavity 13 and a pressure relief hole 14 communicating with the receiving cavity 13. The receiving cavity 13 is generally rectangular, and the electrode assembly 2 is disposed inside the receiving cavity 13. The pressure relief hole 14 is used to quickly discharge the high-pressure gas in the receiving cavity 13 to the outside of the battery cell in the event of thermal runaway of the battery cell.

[0048] The explosion-proof valve 3 covers the pressure relief hole 14 to seal the receiving cavity 13, preventing electrolyte leakage from the receiving cavity 13. Simultaneously, the explosion-proof valve 3 opens for rapid pressure relief in the event of thermal runaway of a single battery cell. Figures 3 to 6 As shown, the explosion-proof valve 3 includes a fixing part 301, a first protrusion 302 and a valve body part 303. The fixing part 301, the first protrusion 302 and the valve body part 303 are integrally formed, and the fixing part 301, the first protrusion 302 and the valve body part 303 are all symmetrical structures extending about the first direction Z.

[0049] The fixing part 301 is fixedly connected to the outer casing 1 or the cover plate 12 to seal the pressure relief hole 14. The valve body part 303 is located on the side of the fixing part 301 closer to the electrode assembly 2 along the first direction Z. The first protrusion 302 connects the fixing part 301 and the valve body part 303, so that the fixing part 301, the first protrusion 302, and the valve body part 303 are integrated. Relative to the fixing part 301, the first protrusion 302 protrudes towards one side of the electrode assembly 2, so that the valve body part 303 is located on the side closer to the electrode assembly 2 relative to the fixing part 301.

[0050] like Figure 6 As shown, the electrode assembly 2 has a base surface 21 that approaches the valve body portion 303 along the first direction Z. The valve body portion 303 has a first surface 3031 that faces away from the electrode assembly 2 along the first direction Z. The maximum distance between the first surface 3031 and the base surface 21 is S1 mm. The fixing portion 301 has a second surface 3011 that approaches the electrode assembly 2 along the first direction Z. The minimum distance between the second surface 3011 and the base surface 21 is S2 mm, satisfying: S1 < S2. When the vehicle is scraped or damaged, the first surface 3031 of the valve body portion 303 is the position on the explosion-proof valve 3 most likely to be impacted. Under the condition of S1 < S2, the first surface 3031 is raised relative to the second surface 3011 of the fixing portion 301, making the valve body portion, a weak part of the battery cell, less likely to be impacted.

[0051] like Figure 4 and Figure 6 As shown, the valve body 303 also has a weak point 304. The weak point 304 is a location with lower strength in the valve body 303. In the event of thermal runaway of a battery cell, high-temperature and high-pressure gas can tear the valve body 303 through the weak point 304, thereby destroying the explosion-proof valve 3 to quickly release the high-temperature and high-pressure gas. The valve body 303 is a relatively weak point in the entire explosion-proof valve 3. By placing the valve body 303 closer to the electrode assembly 2 than the fixed part 301, the distance between the valve body 303 and the outer casing 1 and the cover plate 12 after the battery cell is assembled is increased, thus preventing the valve body 303 from being damaged by impact.

[0052] The explosion-proof valve 3 of the battery cell is formed by a fixing part 301, a first protrusion 302 and a valve body part 303. After the fixing part 301 is fixedly connected to the outer shell 1 or the cover plate 12, since the valve body part 303 is located on the side of the fixing part 301 close to the electrode assembly 2 along the first direction Z, and the maximum distance S1 between the first surface 3031 and the base surface 21 of the electrode assembly 2 is less than the minimum distance S2 between the second surface 3011 and the base surface 21 of the electrode assembly 2, the valve body part 303 is raised relative to the fixing part 301, and the distance between the valve body part 303 and the outer shell 1 is increased, thereby improving the safety boundary when the vehicle is scraped or damaged. This makes the valve body part 303 of the weak part 304 on the battery cell less likely to be impacted, reducing battery cell damage and leakage, and improving the safety of the battery cell.

[0053] In some embodiments, the valve body portion 303 includes a valve body 320 and a reinforcing portion 330 disposed on the valve body 320. The valve body 320 is connected to the first protrusion 302, and a weak portion 304 is disposed on the valve body 320.

[0054] like Figures 7 to 18 As shown, the reinforcing part 330 can improve the overall deformation resistance of the valve body 320, thereby improving the overall strength of the explosion-proof valve 3. In this embodiment, a deformation structure is provided on the valve body 320 to form a reinforcing part.

[0055] In some embodiments, the reinforcing portion 330 further includes a recess 305 and a second protrusion 306. The recess 305 is located on the side of the valve body 320 along the first direction Z close to the fixing portion 301, and the second protrusion 306 connects the recess 305 and the valve body 320.

[0056] like Figures 7 to 10 As shown, the recess 305 is connected to the valve body 320 via the second protrusion 306. That is, the recess 305 is disposed on the valve body 320. The recess 305 and the second protrusion 306 can form a reinforcing structure, enhancing the deformation resistance of the valve body 303 and thus improving the overall strength of the explosion-proof valve 3. In this embodiment, the recess 305 and the second protrusion 306 together form a groove disposed on the valve body 303, and the groove is annular around the first direction Z.

[0057] In some embodiments, along the first direction Z, the distance between the recess 305 and the valve body 320 is L1mm, and the distance between the fixing part 301 and the valve body 320 is L2mm, satisfying: L1 < L2.

[0058] like Figure 10 As shown, the distance L1 between the recess 305 and the valve body 320 is less than the distance L2 between the fixing part 301 and the valve body 320. This ensures that the recess 305 is located on the side of the fixing part 301 that is closer to the electrode assembly 2 along the first direction Z. This increases the distance between the recess 305 and the outer shell 1, ensuring that the valve body 320 and the recess 305 are not easily impacted.

[0059] In some embodiments, the reinforcing portion further includes a second reinforcing rib 307, which is disposed on the second protrusion 306 and connects the recess 305 and the valve body 320.

[0060] like Figure 11As shown, a second reinforcing rib 307 is provided on the second protrusion 306 of the explosion-proof valve 3, and the second reinforcing rib 307 connects the recess 305 and the valve body 320. The second reinforcing rib 307 can increase the internal pressure resistance of the recess 305. The extending direction of the second reinforcing rib 307 intersects the extending direction of the recess 305. The second reinforcing rib 307 and the recess 305 cooperate to increase the deformation resistance of the explosion-proof valve 3 in the valve body 303 and the recess 305. In this embodiment, the projection of the second reinforcing rib 307 along the first direction Z onto the recess 305 is perpendicular to the extending direction of the recess 305.

[0061] In some embodiments, the reinforcing part 330 further includes a third protrusion 308 and a raised part 309. The raised part 309 is disposed on the side of the valve body 320 away from the fixing part 301 along the first direction Z. The third protrusion 308 connects the raised part 309 and the valve body 320.

[0062] like Figures 12 to 14 As shown, the third protrusion 308 protrudes towards the electrode assembly 2, so that the raised part 309 is located on the side of the valve body 320 away from the fixed part 301 along the first direction Z. That is, the raised part 309 is closer to the electrode assembly 2 relative to the valve body 320, which further increases the distance between the raised part 309 and the outer shell 1. The raised part 309 and the third protrusion 308 can increase the overall deformation resistance of the explosion-proof valve 3 and reduce the risk of damage to the explosion-proof valve 3 when the bottom of the vehicle is bumped or hit.

[0063] In some embodiments, the reinforcing part 330 further includes a contoured boss 340, which protrudes toward the electrode assembly 2 along the first direction Z. The contoured boss 340 is either a conical platform or an arc-shaped platform.

[0064] like Figures 15 to 18 As shown, the contoured boss 340 protrudes along the first direction Z of the electrode assembly 2 to form a reinforcing part 330. The contoured boss 340 can be directly formed by processes such as stamping, which is simple to process. In addition, the contoured boss 340 can also reduce the impact of electrolyte on the explosion-proof valve 3.

[0065] In some embodiments, the distance between the raised part 309 and the outer casing 1 along the first direction Z is preferably 0.2mm-4mm. When the distance is too small, the free electrolyte inside the battery cell will submerge the explosion-proof valve 3. When the distance is too large, the explosion-proof valve 3 is prone to damage during the manufacturing process, resulting in a low production yield.

[0066] In some embodiments, the explosion-proof valve 3 further includes a first reinforcing rib 310, which is disposed on the first protrusion 302 and connects the fixing part 301 and the valve body part 303.

[0067] like Figure 11As shown, a first reinforcing rib 310 is provided on the first protrusion 302. After the first reinforcing rib 310 connects the fixing part 301 and the valve body part 303, it can increase the overall strength of the first protrusion 302, thereby increasing the overall deformation resistance of the explosion-proof valve 3.

[0068] In some embodiments, the thickness of the first protrusion 302 is D1mm, and the dimension of the valve body portion 303 along the first direction Z is D2mm, satisfying: D1>D2.

[0069] like Figure 6 As shown, the dimension of the valve body portion 303 along the first direction Z is equal to the thickness of the valve body portion 303. The thickness D1 of the first protrusion 302 is greater than the dimension D2 of the valve body portion 303 along the first direction Z, which increases the strength of the first protrusion 302 and also makes the valve body portion 303 the weakest point of the entire explosion-proof valve 3. In some embodiments, the dimension of the fixing portion 301 along the first direction Z is D3mm, satisfying: D1=D3, so that the overall strength of the fixing portion 301 and the first protrusion 302 is the same.

[0070] In this embodiment, 0.2≤D1 / D3≤0.9. When D1 / D3 is less than 0.2, the thickness of the valve body 303 is small, and the explosion-proof valve 3 is prone to breakage during the manufacturing process, resulting in low production yield and the explosion-proof valve 3 failing the burst test below the threshold. When D1 / D3 is greater than 0.9, the thickness of the valve body 303 and the fixing part 301 are close, the deformation of the valve body 303 is not prominent, and the explosion-proof valve 3 does not meet the application requirements in the burst test.

[0071] In some embodiments, the first protrusion 302 is a tapered protrusion or an arc-shaped protrusion.

[0072] like Figures 15 to 18 As shown, the first protrusion 302 is a conical or arc-shaped protrusion. The conical or arc-shaped protrusion has the function of guiding and relieving pressure, which can reduce the impact of electrolyte on the explosion-proof valve 3. In this embodiment, the included angle between the first protrusion 302 and the fixing part 301 is in the range of 0°-90°. If the included angle is greater than 90°, the explosion-proof valve 3 will be difficult to form in the manufacturing process.

[0073] In some embodiments, the weak portion 304 includes grooves extending about a first direction Z, the grooves being discontinuously distributed.

[0074] like Figure 4 and Figure 8 As shown, the grooves forming the weak part 304 are distributed intermittently. When high-temperature and high-pressure gas tears the valve body part 303 in the weak part 304, the valve body part 303 and the first protrusion 302 remain connected at the intermittent positions of the grooves, which can prevent the valve body part 303 from splashing and damaging the adjacent battery cells.

[0075] In some embodiments, the outer casing 1 includes a housing 11 and a cover plate 12 fixedly connected to the housing 11. The housing 11 and the cover plate 12 enclose a receiving cavity 13. One of the housing 11 and the cover plate 12 is provided with a pressure relief hole 14, which penetrates the housing 11 or the cover plate 12 along the first direction Z.

[0076] In this embodiment, the housing 11 is square with an opening at the top, and the cover plate 12 seals the opening at the top of the housing 11. In some embodiments, such as Figure 1 As shown, the pressure relief hole 14 is located at the bottom of the housing 11, in which case the battery cells are assembled in an upright manner within the battery pack; in some embodiments, such as Figure 2 As shown, the pressure relief hole 14 is located on the cover plate 12. At this time, the battery cells are assembled in the battery pack in an inverted manner to ensure that the pressure relief hole 14 is away from the passenger compartment of the vehicle, thus protecting the vehicle occupants.

[0077] This utility model also provides a battery pack, including a battery cell. The specific structure of the battery cell is the same as that of the battery cell described in any of the above embodiments, and will not be repeated here.

[0078] In summary, this utility model embodiment provides a battery cell and a battery pack, wherein the explosion-proof valve is formed by a fixing part, a first protrusion, and a valve body part. After the fixing part is fixedly connected to the outer shell or cover plate, since the valve body part is located on the side of the fixing part close to the electrode assembly along the first direction, and the maximum distance S1 between the first surface and the base surface of the electrode assembly is less than the minimum distance S2 between the second surface and the base surface of the electrode assembly, the valve body part is raised relative to the fixing part, and the distance between the valve body part and the outer shell is increased, thereby improving the safety boundary when the vehicle is scraped or damaged, making the valve body part, which is a weak part on the battery cell, less likely to be impacted, reducing battery cell damage and leakage, and improving the safety of the battery cell.

[0079] The above description is only a preferred embodiment of the present utility model. It should be noted that for those skilled in the art, several improvements and substitutions can be made without departing from the technical principles of the present utility model, and these improvements and substitutions should also be considered within the protection scope of the present utility model.

Claims

1. A battery cell, characterized in that, The battery cell has a first orientation, and the battery cell includes: The outer casing has a receiving cavity and a pressure relief hole communicating with the receiving cavity; Electrode assembly is disposed in the receiving cavity; An explosion-proof valve is provided, which covers the pressure relief hole. The explosion-proof valve includes a fixing part, a first protrusion, and a valve body. The fixing part is fixedly connected to the outer shell. The valve body is located on the side of the fixing part close to the electrode assembly along the first direction. The first protrusion connects the fixing part and the valve body. The valve body has a weak part. The electrode assembly has a base surface close to the valve body along the first direction. The valve body has a first surface away from the electrode assembly along the first direction. The maximum distance between the first surface and the base surface is S1 mm. The fixing part has a second surface close to the electrode assembly along the first direction. The minimum distance between the second surface and the base surface is S2 mm, satisfying: S1 < S2.

2. The battery cell according to claim 1, characterized in that, The valve body includes a valve body and a reinforcing portion disposed on the valve body. The valve body is connected to the first protrusion, and the weak portion is disposed on the valve body.

3. The battery cell according to claim 2, characterized in that, The reinforcing part includes a recess and a second protrusion. The recess is located on the side of the valve body close to the fixing part along the first direction, and the second protrusion connects the recess and the valve body.

4. The battery cell according to claim 3, characterized in that, Along the first direction, the distance between the recess and the valve body is L1mm, and the distance between the fixing part and the valve body is L2mm, satisfying: L1 < L2.

5. The battery cell according to claim 3, characterized in that, The reinforcing part further includes a second reinforcing rib, which is disposed on the second protrusion and connects the recess to the valve body.

6. The battery cell according to claim 2, characterized in that, The reinforcing part further includes a third protrusion and a raised part. The raised part is located on the side of the valve body away from the fixed part along the first direction. The third protrusion connects the raised part to the valve body.

7. The battery cell according to claim 2, characterized in that, The reinforcing part further includes a contoured boss, which protrudes toward the electrode assembly along the first direction. The contoured boss is either a conical platform or an arc-shaped platform.

8. The battery cell according to any one of claims 1-7, characterized in that, The explosion-proof valve also includes a first reinforcing rib, which is disposed on the first protrusion and connects the fixing part and the valve body part.

9. The battery cell according to any one of claims 1-7, characterized in that, The first protrusion is a conical protrusion or an arc-shaped protrusion.

10. The battery cell according to any one of claims 1-7, characterized in that, The weak portion includes grooves extending around the first direction, the grooves being discontinuously distributed.

11. The battery cell according to any one of claims 1-7, characterized in that, The outer casing includes a housing and a cover plate fixedly connected to the housing. The housing and the cover plate enclose the receiving cavity. One of the housing and the cover plate is provided with the pressure relief hole, which penetrates the housing or the cover plate along the first direction.

12. A battery pack, characterized in that, Includes the battery cell as described in any one of claims 1-11.

Images